Thermal Behavior of Film Cooled Turbulent Boundary Layers as Affected by Longitudinal Vortices

摘要

Heat transfer effects of longitudinal vortices embedded within film-cooled turbulent boundary layers on a flat plate were examined for freestream velocities of 10 m/s and 15 m/s, and for blowing ratios ranging from 0.47 to 1.26. Moderate strength vortices were employed having circulation to freestream velocity ratios of about 1.6 cm. Spatially resolved heat transfer measurements from a constant heat flux surface and mean temperature distributions in spanwise planes show that local heat transfer is significantly affected by spanwise vortex position, and blowing ration. Of particular significance are boundary layer and vortex structural changes which occur at high blowing ratios.